Journal of Machinery Manufacture and Reliability最新文献

This article examines the design of a manipulator model with linear motors that are installed parallel to one axis, which makes it possible to increase the working area along one coordinate. The possibilities of this manipulator getting into special positions of various types are also considered.

The vibrations of a circular, thickness-symmetric three-layer sandwich plate under a local pulsed axisymmetric load are investigated. Thin load-bearing layers obey the classical Kirchhoff hypotheses. In a thicker lightweight filler, the Timoshenko hypothesis is adopted. The effect of temperature on the elastic parameters of the materials of the layer is taken into account. The solution to the initial-boundary value problem for a sandwich plate is obtained by expanding the sought functions in a series over a system of eigenfunctions. Transcendental equations are written out to find the corresponding eigenvalues; their values are given in Table 1. Calculation formulas for deflection and relative shear in the filler are obtained. The results of the numerical analysis are presented in the form of graphs.

The design and calculation of a working environment simulation stand for the in-plant testing of peristaltic pumping units is presented. Such a stand is developed to assess the durability and reliability of the structure through conducting tests under conditions as close to real as possible. In order to confirm the reliability and operability parameters of the structure, a strength calculation has been carried out. The results of the simulation make it possible to confirm the operability of the structure.

Modeling the friction and wear of carbon materials is a complex task, since the materials have unique properties such as high hardness, brittleness, and chemical inertness. In contact pairs, for example, metal–carbon material, complex physical and chemical processes occur, which are associated with the presence of wear products in the contact zone, high temperatures, and a number of other factors. Friction and wear of these materials play an important role in industry: machine tool and engine building, metalworking, and the creation of machine components and mechanisms for various purposes. Regression analysis in modeling friction and wear of carbon materials allows us to identify relationships between various factors influencing these processes. This is necessary for the prediction and optimization of parameters such as friction and wear reduction in various tribological systems, which allows predicting the behavior of the system under different conditions. These are necessary in the development of the materials and technologies under study, which can significantly increase their efficiency and durability.

This article considers the results of experimental deformations of rubber parts of a rubberized-cord toroidal enclosure under compaction by outer and inner steel flanges of an elastic coupling joint. The results of experimenting with one and two monolayers of bearing polyamide cord are presented as graphs of dependences of the frictional coefficient, frictional torque, and slip torque on the applied radial force and compressional deformation of the enclosure by metal flanges. It is shown that the elastic part with two cord monolayers resists the highest load without sliding on exposure to the operating torque with the nominal compressional deformation of the bead parts of the enclosure. The experiments have shown that, in this case, the fatigue cracking on the side surfaces of the rubber part of a coupling joint is less intensive.

The results of tests conducted for different batches of TiNi-based shape memory alloys with various Ti, Ni, Fe, and Co contents are provided.

Among the most rapidly developing areas of modern medicine, minimally invasive surgery occupies a prominent position. One of the modern means of performing operations is the Soloassist® endoscope manipulation system. It is a robotic endoscope holder controlled by a minijoystick attached to the main instrument or by voice commands. The mechanical part of the Soloassist® system has the form of an open kinematic chain. The position problem is to find the rotation angles of the holder given the position of the end point of the tool.

In this paper, the concept of conjugated surfaces is used to reproduce complex spatial surfaces with a tool that also has a complex cutting surface. Universal torus cutting surfaces have been analyzed, allowing us to reproduce convex and concave surfaces with variable radii of curvature. The choice of the position of the cutting edge on the cutting surface is considered in such a way that a universal tool can reproduce complex surfaces with variable radii of curvature.

An overview of the application of artificial intelligence and process control models in mechanical engineering is presented. A number of key aspects are considered, including increasing productivity, product quality, and predicting equipment failures, as well as the prospects and problems of using artificial intelligence in this area. Integration issues and security concerns related to the implementation of artificial intelligence are discussed. Particular attention is paid to the problems of development and application of models of technological process control to improve production efficiency. The role of artificial intelligence in this process is emphasized, and its potential for automation and intellectualization of management is noted. Several important directions for further research are proposed, including the development of more complex and adaptive models, exploration of the possibilities of integrating machine learning methods, conducting experiments in real production conditions, and developing standards for evaluating the effectiveness of control models.

Alongside the maneuvering of spacecraft in the atmosphere, a high intensity of dynamic changes in flight situations also occurs during the active phases of motion of the spacecraft when it is being placed into orbit as an artificial satellite of a planet. Corrective control programs have been developed in the form of functional relationships between control inputs and deviations of trajectory parameters from their nominal values. The use of these programs, combined with calculated analytical dependences, enables the implementation of flight trajectories that are close to optimal disturbed paths, including under conditions of parameter deviations during the atmospheric entry of the spacecraft.